The Dallas route was in 98 & 99 as a summer-only service operated by 767s.
AA have done the ORD route for 24 years (can we have someithing nice on the 25th anniversary please!), having upped frequency to the chagrin of BA who objected to the extra frequencies granted from 1992 to 1995ish (only in the latter year were there extended double daily ops).
JFK was from 1991 to 1994 with a summer-only 1995 before it's return this year
BOS was from 2004 for 3 years as a summer route with MIA operating for 2 years (this route suffered by lack of BA codeshare who thought pax would like to be continued to been inconvenienced by routing through LHR and cruiseliner conctracts not secured).
Granting AA and BA ATI would be the best outcome as there's not a chance BA would open any route outside of London again, and would grant other UK airports the chance of JFK or ORD links. Note, anyone contemplating that BA had no feed ought to consider that BA were feeding AA in JFK. How hard they tried to push the route, as with all routes they operated that were not connected with London, is open to debate.
Slightly more interesting news is that one of the websites carrying the easyJet expansion has "further routes are in the offing" whilst MAN's Andrew Harrison is quoted in another as saying "With more than 5 aircraft here already..."